Reagan National Airport, an official observing site, saw 2.79 inches of rain in just one hour, beating a 1945 record of 2.05 inches, The Washington Post reported.That's climate change for you, after 1 degree globally.
Let's throw the dice and see what its like under 2 degrees, hey my stoopid reader JC?
Update: for anyone who wants to argue about attribution to climate change, as I have recently said in comments, intensification of rainfall is being widely studied and the connection with climate change is clear - it was predicted to increase and it is increasing. If a place breaks a previous rainfall intensity record by a very high margin, then I don't think there is much to argue about in terms of attribution. Have a look at this, for example:
Extreme precipitation has been proposed to scale with the water vapor content in the atmosphere. The Clausius‐Clapeyron (CC) relation describes the rate of change of saturated water vapor pressure with temperature as approximately 7% °C−1 and sets a scale for change in precipitation extremes in the absence of large changes to circulation patterns [Trenberth et al., 2003; Pall et al., 2007]. Analysis of observed annual maximum daily precipitation over land areas with sufficient data samples indicates an increase with global mean temperature of about 6%–8% °C−1 [Westra et al., 2013]. However, observational relations between precipitation extremes and temperature (or dew point temperature) show that subdaily precipitation extremes may intensify more than is anticipated based upon currently available modeling and theory [e.g., Lenderink and van Meijgaard, 2008; Hardwick‐Jones et al., 2010]. This seems to be a property of convective precipitation and may be explained by the latent heat released within storms invigorating vertical motion. This mechanism is thought to generate greater increases in hourly rainfall intensities [Lenderink and van Meijgaard, 2008; Berg et al., 2009; Hardwick‐Jones et al., 2010; Westra et al., 2014; Blenkinsop et al., 2015; Lepore et al., 2015], with a stronger response in convective systems than in stratiform systems [Berg et al., 2013]. This suggests that hourly extremes will probably intensify more with global warming than daily extremes [e.g., Utsumi et al., 2011; Westra et al., 2014].